Preparation and characterization of the polyclonal antibody against pig integrin beta6 subunit LBD as FMDV receptor

Objective: To induce the expression of FMDV receptor integrin beta6 subunit ligand-binding domain in E.coli and prepare the rabbit polyclonal antibody against it.

Methods: The fragment coding beta6 ligand-binding domain was amplified by PCR and doubly digested with BamH Iand Xho I. Then it was cloned into expression vector pGEX-4T-1 to obtain recombinant plasmid pGEX-4T-1-beta6LBD. After pGEX-4T-1-beta6LBD was transformed into E.coli BL21(DE3) and induced by IPTG, the expression of fusion proteins was identified by SDS-PAGE, with inclusion body prepared and fusion protein purified. Then new Zealand rabbits were immunized to prepare polyclonal antibody against beta6LBD. GST-beta6LBD antiserum was obtained and the specificity of polyclonal antibody was detected by Western blot.

Results: SDS-PAGE demonstrated that the fusion protein GST-beta6LBD was expressed with the expected molecular weight at 42 000. A single clear band of GST-beta6LBD fusion protein appeared in SDS-PAGE gel after purification. The titer of the polyclonal antibody was above 1:12 800 and it is of high specificity.

Conclusions: The successful preparation of rabbit anti pig beta6LBD polyclonal antibody with high affinity and specificity will lay a foundation for further research into the function of integrin beta6 in FMDV infection.